Yes, you can sell any emulator that is based on publically available documents or reverse-engineering. it is a software product, as soon as it was a hardware product replicating the original hardware the legal standpoint would be slightly different.
There are zero, nada etc documentation on ps1 that was meant to be public in any way that was the problem, nothing else. You develop for a console through licensing the development including documentation under NDA.
This is not an issue with Amiga, it was publically documented in fact C= made some respectable companies like Addison-Wesley to publish books on amiga hardware and software architecture to promote and help development.
Any computers and system where documentation is publically available can be legally emulated by current laws.
This is very different for systems where development was for a closed circle only.
Also once you made a documentation public in any way its status is public for this matter you can't revoke it by changing your mind even if you wanted to, but you may choose not to publish publically about newer development issues.

And no, Toni does or anyone else does not get paid.
As for patensts and stuff almost all expired on amiga.
Besides many of them including the blitter hardware and other bits and bytes put C= into trouble being violations on someone else's work ath the time they were released
The ks is the result of roughly 3 months of development, and money made with it is not invested into anything whatsoever and never will be.
Games had more years of work invested into them quite often, so worshipping the ks is somewhat laughable, espeically keeping in mind that buying it does not help any other development.

I don't see people crying about games copied freely, so let's just don't be hypocrites at least at Christmas time

But that's not the point here.
We don't want to change your mind in any way, choose what fits you best.
We don't say anything about ks roms, because you can find and download them using google or buy them - it's your choice, not ours. Regardless, since amiga "companies" were made of blind idiots who worshipped the ks fanatically, the only develpment effort they made went into creating massive amount of bullshit for the masses, and trying to find sites supplying ks roms.
So mentioning those put sites into trouble.
We don't want any sort of trouble here, we are not idiots here or deluded people just want EAB to be a safe heaven of nostalgia, not politics and corporate shite or a zealot gathering.
You wanted the truth, you have the truth now. Can you handle it?

If you want it legally buy it, or download/dump the one in your machine. Not anything else exactly the same version.
If you are not that concerned just download anything you want.
None of the money goes to today's amiga development whatsoever.
If you actually want to help that, buy OS4 etc. - things that are being developed and actually some people even paid - minus the constant scandals of developers ripped off even in this small market, but that has never surfaced about Hyperion so they are good guys, unlike many of the others.
And I would say by buying the ks rom you actually help Mike to improve his products. He won't make a new kickstart or os for that matter don't you have illusions about that, but he may try to create some cool stuff that he can put on the cd as a gimmick while the money was actually spent on the "gimmicks" being produced - but many people just want the ks roms anyway